Yamaha DX21 - Manual (Page 40)

MIDI DATA FORMAT
1. Transmission
Conditions
2. Transmission Data
All MIDI data is transmitted when the MIDI ON/OFF function is ON. The MIDI
transmission channel is determined by the setting of the MIDI TRNS CH function.
2-1. CHANNEL INFORMATION
2-1-1. Channel Voice Message
(1) Key Off
Status
Note no.
Velocity
1000nnnn
0kkkkkkk
01000000
n=channel no.
k=36(C1) ~ 96(C6)
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